This invention relates generally to an electric cable system and refers more particularly to a means for re-insulating cable splices and terminations.
High voltage cables used to transmit electric power, and also cables used for low voltage purposes, often require splicing either during installation or when repaired. Insulation or re-insulation of the splice is necessary. Terminations also require that they be insulated when installed or re-insulated at some later time as when repairs are necessary.
In the past, splices and terminations have sometimes been re-insulated with tape. The application of tape is time-consuming and moreover such re-insulation is particularly susceptible to moisture and has a high failure rate when installed underground, especially in the presence of water. Re-insulation by means of a continuous polymer mold has been employed, but requires the use of external heat to achieve the curing or vulcanizing process. A solid dielectric structure is formed that must be bonded to the insulation of the cable to form a moisture barrier and prevent air void formation during electrical load cycling. Such a bond is subject to failure due to expansion and contraction in response to changes in temperature. Two-part epoxy systems have also been used but during thermal cycling and due to expansion and contractions of the bond to the cable, the insulation and the case is often destroyed, creating air space and sites for moisture condensation to form.